1. Field of the Invention
This invention relates to an additive or composition of marble adhesives, and more particularly to an additive capable of enhancing the toughness of marble adhesives.
2. Description of the Related Art
The bonding strength of an adhesive is jointly codetermined by the cohesive strength and adhesion strength of colloid. If the rigidity of the colloid is too strong, the interface for the bonding surface of the adhesive will be damaged; and if the toughness of the adhesive is too great, the cohesion for the bonding surface of the adhesive will be damaged. Therefore, the bonding strength of the adhesive will reach the optimum value only when the rigidity of the colloid is moderate. However, the rigidity of existing marble adhesives is relatively strong, and the bonding surface is easy to release after a long time, thereby damaging the interface and affecting the bonding effect.
At present, the craze of different degrees, appearing in the condensate of marble adhesives, is common. The craze is very similar to the crack, and the difference is that the middle of the crack is hollow, while the middle cavity of the craze is connected by the craze material. The crack grows thickened and forms into the crack by fracturing the craze material. Due to the appearance and development of the craze, the mechanical properties of the material worsen rapidly. In addition, the “ice” phenomenon resulting from the volatilization and auto-agglutination of styrene (cross-linking agent and diluent) in the marble adhesives is common, thereby affecting the operation and use.
Therefore, to develop an additive, which is capable of enhancing the toughness of marble adhesives, and maintaining the moderate strength of marble adhesive and overcoming the “ice” phenomenon and craze of marble adhesives, has become an urgent and important work.